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Amir Akhavanrezayat,1 Wataru Matsumiya,1,2 Prapatsorn Ongpalakorn,1 Hashem H Ghoraba,1 Chris Or,1 Hassan Khojasteh Jafari,1 Gunay Uludag Kirimli,1 Cigdem Yasar,1 Ngoc Trong Tuong Than,1 Irmak Karaca,1 Moosa Zaidi,1 Azadeh Mobasserian,1 Negin Yavari,1 Vahid Bazojoo,1 Yong Un Shin,1 Albert John Bromeo,1 Quan Dong Nguyen1 1Spencer Center for Vision Research, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, USA; 2Department of Surgery, Division of Ophthalmology, Kobe University Graduate School of Medicine, Kobe, JapanCorrespondence: Quan Dong Nguyen, Spencer Center for Vision Research, Byers Eye Institute at Stanford University, 2452 Watson Court, Suite 200, Palo Alto, CA, 94303, USA, Tel +1 650 723 9386, Email ndquan@stanford.eduPurpose: To report a case of neurosarcoidosis (NS) who was initially diagnosed as Coccidioidomycosis immitis (CI) infection.Observations: A 57-year-old diabetic man presented with sudden painless diminution of vision, metamorphopsia, and color vision deficits in the left eye (OS) for one month. His vision was 20/20 in the right eye (OD) and 20/40 OS. Ophthalmic examination revealed left relative afferent pupillary defect, blurred optic nerve margin, creamy chorioretinal infiltration around the optic disc, and mild macular edema. OD examination was non-revealing. Chest CT scan with contrast showed calcified mediastinal lymph nodes, but biopsy of the lymph nodes was normal. Brain and orbit MRI demonstrated soft tissue abnormality with enhancement in left orbital apex with involvement of the extraocular muscles. CSF culture was negative, but complement fixation had positive titer of 1:2 for CI. The patient was diagnosed with CI meningitis, and antifungal therapy was initiated. Slight visual and symptomatic improvement was observed, which was not completely satisfactory. Biopsy of extraocular orbital muscle five months later revealed non-caseating granulomatous inflammation, leading to initiation of prednisone trial therapy. Nine months later, the patient was referred to a tertiary center owing to persistence of optic disc edema OS. PET CT was consistent with a diagnosis of sarcoidosis. Antifungal treatment was discontinued, and oral prednisone with methotrexate was initiated. Subsequently, methotrexate was replaced by infliximab to further manage ocular inflammation and neurologic symptoms which was effective. Vision was 20/20 OD and 20/30 OS at the most recent visit.Conclusion and Importance: Signs and symptoms of neurosarcoidosis and coccidioidomycosis can be similar and deceiving. The index case underscores importance of considering appropriate differential diagnoses in patients with similar symptoms and signs who may respond to preliminary designated treatment but not to the optimal extent. Considering such possibility could assist clinicians in managing the patients timely and efficiently.Keywords: neurosarcoidosis, coccidioidomycosis, sarcoidosis, ocular involvement

Azadeh Mobasserian,1,&ast; Moosa Zaidi,1,&ast; Sohail Halim,1,2 Jaclyn Joyce Hwang,1 Jonathan Regenold,1 Amir Akhavanrezayat,1 Irmak Karaca,1,3 Hassan Khojasteh Jafari,1 Negin Yavari,1 Wataru Matsumiya,1,4 Cigdem Yasar,1,5 Ngoc Tuong Trong Than,1 Gunay Uludag,1 Diana Do,1 Hashem Ghoraba,1 Quan Dong Nguyen1 1Spencer Center for Vision Research, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, USA; 2Ocular Imaging Research and Reading Center, Sunnyvale, CA, USA; 3Department of Ophthalmology, Ege University Faculty of Medicine, Izmir, Turkey; 4Division of Ophthalmology, Department of Surgery, Kobe University Graduate School of Medicine, Kobe, Japan; 5Department of Ophthalmology, Suleyman Demirel University, Faculty of Medicine, Isparta, Turkey&ast;These authors contributed equally to this workCorrespondence: Quan Dong Nguyen, Spencer Center for Vision Research, Byers Eye Institute, Stanford University School of Medicine, 2370 Watson Court, Suite 200, Palo Alto, CA, 94303, USA, Tel +1 650 725-7245, Fax +1 650 736-8232, Email ndquan@stanford.eduPurpose: Diopsys® NOVA fixed-luminance flicker full-field electroretinogram (ffERG) device is a potential adjunct to conventional flicker ffERG testing for assessing cone cell function. Magnitude of measured electrical response is known to vary with pupil size in conventional ffERG testing. The index study characterizes the relationship between magnitude of measured electrical activity and pupil size, both pupil diameter and pupil area, for this device.Methods: Seventeen patients (34 eyes) with no known ocular diseases were enrolled in the study. Electrophysiologic function of cone cells was evaluated using fixed-luminance flicker ffERG before and after dilation. Linear regression models, with inter-eye correlations controlled as fixed-effects, were used to characterize the effect of pupil dilation on the magnitude of the measured responses.Results: Mean age of study patients was 33.5 (standard deviation 7.4 years), and 35.3% of the subjects were female. Mean value of electrical response magnitude was 10.07± 2.79μV before dilation and 15.30± 4.08μV after dilation. The correlations of ERG magnitude with pupil diameter and with pupil area were not significant for either dilated or undilated eyes considered separately but were highly significant (p< 0.001) for dilated and undilated eyes considered in aggregate. ERG magnitude tended to increase by 1.08 μV for every 1 mm increase in pupillary diameter.Conclusion: An increase in pupil size, both pupil diameter and pupil area, is significantly associated with an increase in flicker ffERG magnitude recorded by the Diopsys device, suggesting that pupil size should be measured and considered when making clinical judgments based on the flicker ffERGs recorded by the device, and that pupil size-specific reference ranges could improve the clinical utility of the device.Keywords: electroretinogram, ERG, flicker ERG, pupil, magnitude, Diopsys

In this paper, we study the two-parameter spectral element method based on weighted shifted orthogonal polynomials for solving singularly perturbed diffusion equation on an interval [0, 1] which are modeled with singular parameters. We continue our study to estimate the lower bound of the weighted orthogonal polynomial coefficient and the upper bound of a posteriori error estimates of the method through different weighted norms to minimize the computational cost. Numerical examples are implemented to study the applicability and efficiency of the technique. The obtained error bounds for the coefficient of orthogonal polynomials and the posteriori estimates fall within the bounds derived in the theoretical section. It is also observed that the two weighted norms decreases when the values of N 1 and N 2 increases for the three choices of and for different values of x and y. The quality and accuracy of the solution can be realized through figures and tables. [ABSTRACT FROM AUTHOR]

In this article, a numerical method is presented for solving non-linear multi-order fractional differential equations (FDEs) using orthonormal Boubaker polynomials as basis functions. The operational matrix is constructed for the product of basis functions. The fractional derivative is considered in the Caputo sense. Using this technique, non-linear multi-order FDEs converted into a system of non-linear algebraic equations, which can then be solved numerically. The proposed method is implemented using MATLAB for numerical analysis. Using numerical results, validity, and accuracy of the proposed method is given and compared the results with existing literature. [ABSTRACT FROM AUTHOR]